In the process of fabricating thin film transistors (TFTs) on a substrate, processes such as photoresist coating, exposure, development and etching are performed. The development process is mainly employed to remove the photoresist retained on the substrate subjected to the exposure process to pre-form a required pattern for a subsequent etching process.
Generally, a spray type developing system is employed in the prior art. In such developing system, a plane where a substrate is located is in parallel with a conveying direction, and the substrate is tilted at a certain angle (typically, a fixed value) with respect to a horizontal plane, in order that developer on the substrate can flow off the substrate as quickly as possible. As such, a lower portion of the substrate receives more developer than an upper portion of the substrate, resulting in an uneven development, which in turn affects uniformity of a line width of pixel (i.e., an actual transmittance width of a sub-pixel unit subjected to the development) and results in abnormal quality issues such as light leakage. Moreover, a motor is required to drive the substrate to be tilted at a certain angle, which takes a long time and thus lowers efficiency of production line.